def Qmax_cut(self, w: List[List[int]], ans_set)->List:
        qubitOp, offset = max_cut.get_operator(w)

        # mapping Ising Hamiltonian to Quadratic Program
        qp = QuadraticProgram()
        qp.from_ising(qubitOp, offset)
        qp.to_docplex()#.prettyprint()

        # solving Quadratic Program using exact classical eigensolver
        exact = MinimumEigenOptimizer(NumPyMinimumEigensolver())
        result = exact.solve(qp)

        return result
Пример #2
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    def calculate(self, G, cost_matrix, starting_node=0):

        # Create nodes array for the TSP solver in Qiskit
        coords = []
        for node in G.nodes:
            coords.append(G.nodes[node]['pos'])

        tsp_instance = tsp.TspData(name="TSP",
                                   dim=len(G.nodes),
                                   coord=coords,
                                   w=cost_matrix)

        qubitOp, offset = tsp.get_operator(tsp_instance)

        backend = Aer.get_backend('qasm_simulator')
        quantum_instance = QuantumInstance(backend)

        optimizer = COBYLA(maxiter=300, rhobeg=3, tol=1.5)

        # Define Minimum Eigen Solvers
        minimum_eigen_solver = QAOA(quantum_instance=quantum_instance,
                                    optimizer=optimizer,
                                    operator=qubitOp)
        #minimum_eigen_solver = VQE(quantum_instance=quantum_instance, optimizer=optimizer, operator=qubitOp)
        exact_mes = NumPyMinimumEigensolver()

        # Create the optimizers so we can plug our Quadratic Program
        minimum_eigen_optimizer = MinimumEigenOptimizer(minimum_eigen_solver)
        #vqe = MinimumEigenOptimizer(vqe_mes)
        exact = MinimumEigenOptimizer(exact_mes)
        rqaoa = RecursiveMinimumEigenOptimizer(
            min_eigen_optimizer=minimum_eigen_optimizer,
            min_num_vars=1,
            min_num_vars_optimizer=exact)

        # Create QUBO based on qubitOp from the TSP
        qp = QuadraticProgram()
        qp.from_ising(qubitOp, offset, linear=True)

        result = rqaoa.solve(qp)

        if (tsp.tsp_feasible(result.x)):
            z = tsp.get_tsp_solution(result.x)
            print('solution:', z)
            return z
        else:
            print('no solution:', result.x)
            return []
Пример #3
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    def calculate(self, G, cost_matrix, starting_node = 0):

        # Create nodes array for the TSP solver in Qiskit
        coords = []
        for node in G.nodes:
            coords.append(G.nodes[node]['pos'])

        tsp_instance = tsp.TspData(name = "TSP", dim = len(G.nodes), coord = coords, w = cost_matrix)

        qubitOp, offset = tsp.get_operator(tsp_instance)
        print("Qubits needed: ", qubitOp.num_qubits)
        #print(qubitOp.print_details())

        #backend = Aer.get_backend('statevector_simulator')
        backend = Aer.get_backend('qasm_simulator')

        # Create QUBO based on qubitOp from the TSP
        qp = QuadraticProgram()
        qp.from_ising(qubitOp, offset, linear=True)

        admm_params = ADMMParameters(
                            rho_initial=1001,
                            beta=1000,
                            factor_c=900,
                            maxiter=100,
                            three_block=True, tol=1.e-6)

        qubo_optimizer = MinimumEigenOptimizer(QAOA(quantum_instance=backend))
        convex_optimizer = CobylaOptimizer()
        admm = ADMMOptimizer(params=admm_params,
                             qubo_optimizer=qubo_optimizer,
                             continuous_optimizer=convex_optimizer)

        quantum_instance = QuantumInstance(backend)

        result = admm.solve(qp)
        print(result)
Пример #4
0
                     ax=default_axes,
                     pos=pos)
    edge_labels = nx.get_edge_attributes(G2, 'weight')
    nx.draw_networkx_edge_labels(G2,
                                 pos,
                                 font_color='b',
                                 edge_labels=edge_labels)


qubitOp, offset = tsp.get_operator(ins)
print('Offset:', offset)
print('Ising Hamiltonian:')
print(qubitOp.print_details())

qp = QuadraticProgram()
qp.from_ising(qubitOp, offset, linear=True)
qp.to_docplex().prettyprint()

result = exact.solve(qp)
print(result)

ee = NumPyMinimumEigensolver(qubitOp)
result = ee.run()

# print('energy:', result.eigenvalue.real)
# print('tsp objective:', result.eigenvalue.real + offset)
x = sample_most_likely(result.eigenstate)
print('feasible:', tsp.tsp_feasible(x))
z = tsp.get_tsp_solution(x)
print('solution:', z)
print('solution objective:', tsp.tsp_value(z, ins.w))